Loop retainer for sewing machines



Feb. 19, 1929.

J. R. MOFFATT LOOP RETAINER FOR SEWING MACHINES Filed April 2, 1925 .sSheets-Sheet 1 Feb. 19, 1929. 1,702,792 J. R. .MOFFATT LOOP RETAINER FORSEWING MACHINES Filed April 27, 1925 s Sheets-Sheet 2 Feb. 19, 1929.1,702,792

J. R. MOFFATT LOOP RETAINER FOR SEWING MACHINES Filed April 27, 1925 sSheets-Sheet Patented Feb. 19, 1929.

' UNITEDSTATES 1,702,792 PATENT OFFICE;

JAMES, R. MOFFATTy OF CHICAGO, ILLINOIS, ASSI GNOR TO UNION SPECIALMACHINE COMPANY, OF CHICAGO, ILLINOIS, CORPORATION OF ILLINOIS.

LOOP RETAINER FOR SEWING MAonrNEs.

Application filed April 27, 1925. Serial No. 26,1529.

The invention relates to new and useful im provements in loop retainers.for sewing machines, and more particularly to a loop retainer used forholding the needle thread loops back on the looper inamultiple threadsewing-machine, wherein a single looper cooperates with aplurality ofneedles.

An object of the invention is to provide a loop retainer which is notonly movable over the upper face of the looper but also longitudinallyof the looper to aid in positioni'ng and holding back certain 01? thenee? dle thread loops on the looper so as to 'insure that the needleswill enter their respec tive thread triangles in the forming of thestitches.

A further object of the invention is to provide loop retainers whichderive their movement troma feeding mechanism, which provides a verycompact mechanism which may be readily used in a cylinder bed machine,where the tubular articles are formed and led oil from the end of thearm.

These and other objects will in part be obvious and will in part behereinafter more fully disclosed.

In the drawings which show by way of illustration one embodiment of theinvention Figure Tie a View partly in section and partly in sideelevation ofa portion of a sew in; machine embodying my invention Fig. 2is a sectional view on the line 2-2 of Fig. 1;

Fig. 3 is a plan view of a portion of the work supporting arm withportions of the feeding mechanism removed so as to show the loopretainers and'the manner of operating the same;

Fig. 4 is a detail in section showing the needles, the looper. the endof the "feed bar and the loop retainers and the means for sup-- portingand operating the same; the section is on the line 4t4t oi Fig. 5;

Fin. is a plan view with the parts shown "and looper posiin Fig. l, withthe needleslion as shown in said figure 6. is a view similar to Fig. 4.but with the looper at the forward end o'f'its stroke the feed barraised, and the loop retainers at the right-hand end of their movement,but not yet moved across the looper, the section in tl'iis figure is onthe line 6 6 of 7, and,

Fig. 7 is a plan view of the parts as positioned in Fig. 6.

The invention has to do broadly with loop retainers for a multipleneedle machine-v and preferably a three-needle machine, set abreast, andwith which asingle thread carrying looper cooperates- This looper movesforward into the needle thread loo'psone'after another. It is then movedlaterally for its needle avoidingmovement, and the needles enter theirrespeotive triangles.

Referring to the needles as needle-No. 1, which is next to the loopereye when the looper is at the forward end of its stroke; the

middle needle as No. 2', and the other needle as No. 3. Needle No. 1should pass between the thread triangle formed by the loop of thisneedle on the looper and the thread of the looper extending from the eyeto the previous concatenation-pt the needle thread loops and looperthread. Needle No. 21 should pass with certainty between its own needlethread loop on the looper, and the thread of the looper running from theeye thereof to the previous concatenation of the threads, and also inrear ofthe needle thread loop of needle No. 1. Needle No. should pass infront of its own needle. thread loop on the looper, and. in rear of theneedle thread loop of" needle No; 2. It is well known that these needlethread loops on the looper, when the looper i-s retracted, are draggedbythe looper rearwardly, but there is no positive way of keeping theneedle thread loop on the looper separated. Prior to my invention, loopretainers have been provided for holding these needle thread loopsseparated. One instance is shown in the patent toKaa'l. Maier#1,098,8:14, granted June 2, 1914.

The present invention has to do with. an improvement in the manner ofmounting loop retainers o the type shown in this Maier patent, so as toenable the loop retainer to be used in connection with a cylindermachine;

and so as to enable the retainers tooperate to further separate theneedle thread loops so as to give ample clearance space for the needlesto enter their respective thread triangles even though the needles beset very closely together- The loop retainers are given fourmovernentsone a movement forward across the looper; then a movementrearwardly of the looper, that is. toward the-heel of the looper.wl'iieh carries the needle thread loops engaged llwreby liaclm'ard onthe looper to a certain extent, and then a movement to a position wherethe needle thread loops may pass the loop retainers, and finally, amovement in a direction tori ard of the looper to its initial positionfor its next cycle of move ment. This loop retainer consists of an armor bracket carrying linge s or projections which cooperate .vith therespective needle thread loops engaged thereby. This arm or bar iscarried b a sleeve mounted to swing about an axis on which the looperoscillates as it moves into and out of the needle thread loops. Thissleeve also moves endwise 01 its support, and thus the aour motions areimparted thereto.

'l'lie ese iilating movement of the sleeve carries the lingers backward.and forwardly longitudinally oi the looper. and the endwise moven'ientoi the sleeve carries said lingers across the looper and retracts it toa position clear of the looper. This sleeve is moved. by the arm whichis connected with the feed bar. The up and down movements of the feedbar moving the feed dog into and out of engagement with the fabric.oscillate the sleeve, and the endwise movement of the feed bar moves thesleeve endwise on its support.

Referring more in detail to the drawings, my impro -ned loop retainersare shown as ap plied. to a feed-otT-the-arm mach ne which includes awork supporting cy. ..nder arm. 1 in, which is mount d a loopersupporting; shaft 2. Above the looper supporting; shaft 2 is a feed bar3 which is provided with a main feed dog l: and a differential feed dog5. The feed bar 3 is moved endwise ot the work supportarm for imparting;feed movements to the food dogs and it is raised and lowered in the armfor moving the "feed dogs into and out of engagement with the fabric.The feed ing mechanism is in ,general of the type shown in. the palentto Joseph Berger alrLi-llQfiQS, granted August 12 L919, and furtherdescription lhereo'l is not thought necessary. Co- ()pfll'fllili'lg withthese feed dogs is a presser foot 6 car fied by a. presser bar 7. Themachine may be equipped with trimming devices tor trimming the fabricedges, which hibric edges are adapted to be abntted or overlapped andowed by a flat seam as disclosed in said patent To this end. the nmchineis provided with a reciprocating; needle bar 8 carrying three needles 9.l0 and ll. These needles are set abreast that is, in a plane at rightangles to the line of feed, and cooperatin; with all t hree needlesbeneath the throat plate irulhiated at 12 is a thread carrying looper13. This thread carrying looper 13 is mounted on the looper supportingshaft 9 and 1 s the shaft oscillates, it will move the looper first intothe needle thread loop of the needle 9. then into the thread loop of theneedle 10. and then into the thread loop ol the needle ll, so the t allthree needle loops are engaged by this one looper. This is clear- 13shown in Figure 4: and 6 or the drawings. The looper as it is retractedis moved laterally indicated in Fig. 5 of the drawings,

that the needles on their downward-movement. will pass on the other sideof? the looper. The feed is oil the end oi? the arm, and therefore. thethread (it the looper running from the eye thcreoili, and to theprevious coner. nation oi? the thread loops will extend toward the endof the arm. The needle thread loops on the looper will have their shanksalso extending toward the end of the work supporting arm. In Figures land 6 of the drawings, have shown diagrammatically the needle thre: dloops on the looper. in llip; 6., the looper is at the forward end ofits st .ohe; while in Figures 4 and 5, the looper has been retracted andthe retainers forming the present invention have engaged the twolelthand needle loops, and pushed them back on the looper. The looperthread is indicated at 14:. The needle thread loop of the needle 9 isindicated at 15; the needle thread loop of the needle 10 at 16; and theneedle thread loop ot the needle 11 at 17. The needle thread loop 17will be properly held bacl: on the looper by reason of the fact that thelooper FlflJElGGlll) its eye is wlder or in? than farther back on thelooper, and

while the loop mayslip forward on the looper as is retracted, it will bedragged back srrtliciently so that the needle 11 will with surety passin front of the needle thread loop 1.7. and into the triangle formed bythis needle thread loop 17. the body of the looper and the looperthread. ll (see Fig.

In order to hold the loops 15 on the looper, and to further crowd them.bacl: to a. certain extent so that they will he properly spaced fromeach other and from the needle thread loop 17, l have provided. two loopretainers l8 and The loop retainer 18 as clearly snown in ligrures 4-and 5 oi the drawing: is in front oi the needle thread loop 1.53. anddeflecting or crowding the same rearward on the looper and thus opening:wide the triangle 'lorme... by this needle thread 18. the body oi theloop-er. and the looper thread '14-. l iiliewise. the reminer 19 engagesa needle threadle-op l6. and holds the some baelr on the looper and wellaway from the needle thread loop so that the needle 10 will withcertainly enter its triangle il orined by the needle thread loop ll),the body oil the loopor. and the. looper thread. 14:. The two retainersl8 and ll) also hold the thread loops 15 and 16 properly spaced fromeach. other, so that the needle 9 will pass between these needle threadloops 15 and 16. This insures a perfectly concatenate-d three-needlefiat seam, wherein the needle thread loops are all locked by a singlelooper thread.

In order to impart to these retainers ll-l an d 16 back and 19 theirproper movements, said retainers or fingers are carried-by a member 20'which is integral with anarm'21 carried by a sleeve 22. The arni'21 isbent later-allyat its upper end to form themember 20, and at the outerend o'f'thisl arm, are the retainerfingers 1'8 and 19. The-sleeve 22 ismounted on the looper supporting shaft 2, and is free to oscillatethereon, and also to move endwise thereof, so that the loopersupportingshaft serves merely as a supportfor the sleeve.

Thesleeve has a laterally projecting arm 23 with ball head 24 on the endthereof. ls l'ounted. on the end of the main feed bar 3 is a bracket armSaid arm extendslaterally of thefeed to a position at one side of;the-'loo1: e 1-supporting shaft 2'. Said bracket armat its lower end hasa recess which receives the ball 24, This bracket arm 25 moveswiththefeed bar, and therefore, it has movement backward and forward inad irection lengthwise ofthe work supporting arm, which is in adirection longitudinally of" the looper sup porting shaft, and at rightangles tothe-plane of movement of the looper. It also has a movement upand down as-the feed dog is moved into and out of engagement; with thematerial, which is caused-by the up-an'd down movements of the end ofthe feed bar. The

up and down movements ofithe" feed bar, I

therefore, through the arm 23, will oscillate the sleeve 22, whi l'ethebackward and forward movements of the feed har,through this bracket 25'and the arm- 23, will move the sleeve in an endwi se direction,andthis,as. has been-stated, causes the retainer fingersto.

move across the loopertoa sufficient extent to engage the needle loopsthereon, while the:

rocking of the sleeve moves the fingers.

toward the rear-end of the looper, and. this causes the fingerstoengagethe needle thread loops on the looper and move the same towardthe rear end of the l'ooper.

The operation ofthe improved loop-retai ncrs is as follows: WVhenthe-looper moves.

into the needle thread-loops, itmoves forward tothe endofi ts stroke; Atthis time, the

looper is fully into the needle thread loops, and the needles are at:theiextreme upper end:

of their stroke. Asthellooper startsto re tract, it begins its lateral:movement, andthe lateral movement of the looper is toward the arm 21,and underneath the retainer-fingers 18 and 19. Just asthe-l'ooper isreaching the forward end of its streke,-' the feed: stroke 'oea ours andiscomplet'ed Thisfor-wardmovea. ment of the feed bar moved the sleeve 22forward on the loopersupporting; shaft 2,

and moved the. retainers 118 and 19 over the.

looper, so thatthe combined". forward move: ment ofthe retainer fingersand lateral move ment' of the looper, moves.- these retainers in:between theneedle threaddo opson the looper, as shown r in Fig.fi-ofthe. drawings The bar, and thence downwardly feed; dog is nowlowered for its retracting movement, and the lowering of the feed. dog

will oscillate the sleeve 22 to the. left as viewed in'Fig. &, and willmovexthe retainers 18 and 19 toward the heel of thelooper- This not onlybrings the retainers which. were in front of the'needle thread'loopsinFig. 6 backward into engagement with the loops, but will alsocrowd theloops back on the looper, or deflect the threads. between the shanks ofthe respective loops and the looper so as to'give ample room fortheneedles 9 and 10 to enter their respective thread triangles as abovedescribed. During the retracting movement of the feed dog, the loopretainers are also'moved therewith frombetween the needles,-and afterthey are entirely clearof the needles, they are again oscillated: tovthe right as viewed in Fig. 4, back to the position shown in Fig. 6, andthis is broughtabout by the raising of the feed dog into engagement withthe fabric.

From the above it-will be noted that I have:

needle; thread loops, and. positioning the.- same, and- Which are movedbackwardly from over the loopersand then forwardly to their initialstarting position intheir cycle of movement. vided: loop retainersespecially adapted fora cylinder bed machine, which may be packed intheendof a cylindrical arm and operated the feeding mechanism therein.

Likewise, I have pro when moving into engagement with the While I havedescribedlmy improved loop retainer operating mechanism. as especiallyadapted to be used? in connection with a, cylinder' bed machine, it willbe understood that it may,-however, be used in other types of machines,such as a flat bed machine, in which case, of course, the looper wouldmove at right angles tothe line of feed, as in the present case, and theretainers would be operated in conjunction with the loopers by the upanddown movement of the feed oscillating the retainers or moving themtowardand from theheel of the looper, while the movement of these retainerstowards and across the loopers and back therefrom would boderiveol'fromthe lengthwise or feedingv movements of the feed bar. While I havedescribed the sleeve carrying the loop retain- .ers as mounted on thelooper supporting shaft, itwill beunderstood'that this is mere .ly. aconvenient support for said sleeve, and

said sleeve. mightbe mounted otherwise, In

other words, the fact that the present support of the sleeve alsosupports the looper, does not in any way affectthe function of thelooper or affect the function of the loop retainers. It is merely asupport for the loop retainers.

It is obvious that minor changes in the details of construction and thearrangement of the parts may be made without departing from. the spiritof the invention as set forth in the appended claims.

Having thus described the invention, what I claim as new and desire tosecure by Letters-Patent, i s

1. in a sewing machine, the combination. of a feeding mechanismincluding a feed bar, a feed dog carried thereby, a'plurality of needlesset abreast, an oscillating thread carrying looper cooperating with theneedles, loop retainers, means independent of the feed bar forsupporting said loop retainers, means operated by the up and downmovement of the feed bar for moving said thread retainers in a planeparallel with the plane of oscillation of the looper, and means operatedby the endwise movement of the feed bar for mov ing said retainers in apath substantially at right angles to the plane of oscillation of thelooper.

2. Asewing machine inchiding in combination, a cylindrical worksupporting arm, a

looper supporting shaft located in said arr and extending lengthwisethereof, a looper rigidly mounted on said shaft and adapted to oscillatetransversely of the work supporting arm and move laterally in said armfor a needle avoiding movement, loop retainers associated with saidlooper, a sleeve mounted on the looper supporting shaft carrying saidre;ainers, said sleeve being free to oscillate and move endwise on saidshaft, and devices connected to said sleeve for moving the same endwiseand oscillating said sleeve for imparting movements to the retainerscarried thereby for causing said retainers to engage and. hold theneedle thread loops on the loopor spaced and positioned for the needlesto pass.

3. A sewing machine including incomhination, a cylindrical worksupporting arm,

a plurality of needles sot abreast and operating at the end of said worksupporting arm, a looper shaft extending lengthwise thereof, a loopsn'rigidly mounted on said shaft, :1 feed bar extending lengthwise of slidarm, and having a back and forth and an up and down movement, asleevefreely mounted on said looper supporting shaft, loop retainers mountedon said slecvc'and cooperating with said looper, an arm extendinglaterally from said sleeve, a bracket arm extending laterally from saidfeed bar and having adepending portion connected to said arm on thesleeve whereby the back and forth movements of the feed bar impartendwise movement to the sleeve carrying the retainers and whereby the upand down movements of the feed bar impart an oscillating movement tosaid sleeve.

4:. A sewing machine including in combi nation, a cylindrical worksupporting arm, a looper shaft extending lengthwise thereof, a singlethread carrying looper mounted on saidshaft and adapted to operatetransversely of said arm and move sidewisefor a needle avoidingmovement, a plurality of needles with which said looper cooperates,-afeed bar extending lengthwise of said work supporting arm and having aback and forth and an up and down movement, a sleeve mounted on thelooper supporting shaft, loop retain ers mounted on said sleeve, an armpro ect1ng late 'ally from the sleeve, a bracket arm projectinglaterally from the feed bar and connected to said arm whereby when saidfeed bar is moved endwise for feeding the material along the worksupporting arm, said retainers are moved toward and across the upperface of the looper, and whereby when said feed bar is lowered, saidlooped retainers are moved lengthwise of the looper, and caused toengage the needle thread loops on the looper for holding the sameseparated and properly positioned for the needles to pass.

5. In a sewing machine, a cylindrical work supporting arm, a feed barextending lengthwise of the arm, a feed dog carried thereby, said feedbar having a back and forth and an up and down movement for impartingfour motions to the feed dog, a needle, a thread carrying loopercooperating with the needle and movable in a plane substantially atright angles to the longitudinal axis of the feedbar, a loop retainerassociated with said looper, and means whereby the back and forth and upand down movements of the feed bar impart movements to the retainerlengthwise of and transversely of the looper. I l

6. In a sewing machine, the combination of a feeding mechanism includinga feed bar adapted to be moved back and forth and raised and lowered, afeed dog carried thereby, a plurality of needles set abreast, anoscillating thread carrying looper coperating with the needles, loopretainers, means for supporting said loop retainers whereby they may bemoved ina direction substantially parallel with the path of the looperand in a direction substantially at right angles to the path of thelooper, and means operated by the feed bar in its back and forth and upand down movements for imparting the movements to the retainers.

7. In a sewing machine, the combination of a feeding mechanism includinga feed bar adapted to be moved back and forth and raised and lowered, afeed dog carried thereby, a plurality of needles set abreast, an.oseillating threadcarrying looper cooperating with the needles, loopretainers, means-for supporting said looped retainers whereby they maybe moved in a direction substantially said retainers transversely of thelooper and parallel with the path of the looper and in a rearwardly ofthe looper for engagement 1 direction substantially at right angles tothe With the needle loops, and thence transversely path of the looper,and means operated by of the-looper and forwardly of the looper to 5 thefeed bar in itsback and forth and up release said needle thread loops.

and down movements for imparting the move In testimony whereof I afiixmy signature.

ments to the retainers, said operating means. for the retainers beingtimed so as to move JAMES R. MOFFATT.

